LISBON, PortugalThe combination of capecitabine (Xeloda) and
oxaliplatin (investigational in the United States) produced a 55% response rate
in a phase II study of patients with advanced or metastatic colorectal cancer,
Chris Twelves, MD, of Beatson Oncology Centre, Glasgow, Scotland, said at the
11th European Cancer Conference (abstract 1005). In addition, he said, 32% of
patients in the study had stable disease.
Capecitabine is a novel oral fluoropyrimidine that is converted to
fluorouracil (5-FU) at the tumor site by exploiting the higher activity of
thymidine phosphorylase in malignant tissue, Dr. Twelves said. "It has
demonstrated superior activity and an improved safety profile, compared with IV
bolus 5-FU/leucovorin (Mayo Clinic regimen) in two large phase III
trials," he said.
The current open-label, single-arm study enrolled 96 patients at 13 centers
in eight countries. Patients received oral capecitabine, 1,000 mg/m² taken at
home twice daily on days 1 to 14 of a 3-week cycle, and a 2-hour infusion of
oxaliplatin, 130 mg/m² on day 1.
Dr. Twelves emphasized that patients on this regimen spend only a few hours
in the clinic each month. In contrast, 5-FU/leucovorin is given as a continuous
infusion for 48 hours every 2 weeks.
He pointed out that the 55% response rate was consistent across all
subgroups, including patients with liver and lung metastases, patients who had
received primary adjuvant chemotherapy, and patients with lower performance
status. The average duration of response, he said, is currently 8 months, and
the median time to progression is 7.1 months. Median survival, he noted, had
not been reached 15 months after the start of the trial and 7 months after
enrollment of the last patient.